An 846 · Inventory Inquiry/Advice is the document a seller or warehouse uses to tell a buyer what inventory exists, where it is, and in what condition — on hand, committed, on order, or damaged — before the buyer places an order against stock that may not be there. It answers the question every 850 · Purchase Order silently assumes: is there anything to buy?
I run SignalEDI. This series has walked the order-to-cash chain in order — the 850 · Purchase Order, the 855 · Purchase Order Acknowledgment, the 856 · Ship Notice / ASN, the 810 · Invoice, and the 997 · Functional Acknowledgment that proves a file parsed. The 846 sits before all of them. It is the feed that makes the rest of the chain honest, because an order placed against phantom inventory fails expensively, in public, at the worst possible moment.
What is an 846 · Inventory Inquiry/Advice?
It is the X12 transaction set used to communicate inventory position between trading partners. Despite the name, in practice it is usually sent as advice — a seller, manufacturer, or third-party warehouse pushes its current inventory picture to a buyer, a retailer, or a marketplace on a schedule, rather than waiting to be asked.
The detail is item by item and, crucially, location by location. For each item at each warehouse or store, the 846 reports quantities broken down by status: quantity on hand, quantity already committed to other orders, quantity on order from the supplier's own supply chain, and quantity that exists physically but cannot be sold — damaged, held for quality inspection, or otherwise unavailable. That status breakdown is the entire value of the document. A single "we have 500" number is almost useless; "500 on hand, 380 committed, 100 on order arriving next week, 20 damaged" is a buying decision.
How is an 846 different from an 850 and an 855?
These documents answer questions at different points in time. The 846 answers "what do you have, right now and in the near future?" — before any order exists. The 850 · Purchase Order answers "here is what I want to buy." The 855 · Purchase Order Acknowledgment answers "here is what I will actually do about that order, line by line."
Read together, they form a chain of narrowing promises. The 846 is a statement of position, not a commitment — inventory can move between the feed and the order. The 855 is the commitment. Trouble starts when a buyer treats an 846 as a reservation: it is not one. It is a snapshot with a timestamp, and the discipline is in how fresh that snapshot is and how honestly the committed and unavailable quantities are reported.
Why does stale inventory data cause chargebacks?
Because the failure surfaces downstream, where it is expensive. A buyer orders against a week-old 846 that showed plenty of stock. The seller short-ships or cancels. The retailer's shelf or promotion fails, and the resulting chargeback, expedite cost, or lost placement lands on the seller — even though the root cause was an inventory feed nobody refreshed.
The same pattern hits drop-ship programs hardest. A retailer lists a supplier's products based on the supplier's 846 feed; a consumer buys; the supplier is actually out of stock; the cancellation and the customer-service cost belong to the retailer in the consumer's eyes, and to the supplier in the retailer's scorecard. In drop-ship, the 846 is not back-office plumbing. It is the product listing's source of truth.
What should a good 846 feed get right?
Send it on a schedule the buyer can plan around, and more often when inventory moves fast — a daily feed for slow movers and an intraday feed for promoted items is a common, sensible split. Report committed and on-order quantities, not just on-hand: a buyer who can see that stock is thin but replenishment lands Thursday makes a different decision than one who only sees "low." Mark unavailable stock explicitly instead of quietly subtracting it, because a sudden unexplained drop looks like a data error and gets investigated as one. And keep the item and location identifiers exactly as the buyer orders them — an 846 keyed to a different warehouse code or a supplier-internal SKU that does not match the buyer's item file is a feed that reconciles with nothing.
What should buyers do with an 846?
Treat it as perishable. Record when each feed arrived, age the data visibly, and tighten reorder rules as the snapshot gets older. Reconcile it after the fact, too: compare what the 846 promised against what later 855 acknowledgments confirmed and what 856 shipment notices actually shipped. A supplier whose 846 consistently overstates available stock has a data problem you can prove with that three-way comparison — and proving it with documents ends arguments that opinions cannot.
Frequently asked questions
Is the 846 a commitment to hold stock?
No. It reports inventory position at a moment in time. The commitment in the order cycle is the 855 · Purchase Order Acknowledgment, sent in response to a specific 850 · Purchase Order.
How often should an 846 be sent?
As often as the inventory materially changes, on a predictable schedule. Daily is a common baseline; high-velocity and promotional items often justify intraday updates.
Can a warehouse or 3PL send the 846 on a seller's behalf?
Yes — that is a common pattern. The warehouse holds the physical truth, so having the 3PL originate the feed (as it often does with the 856) removes a hand-off where numbers go stale.
The pattern across this series holds again: each EDI document answers exactly one question well. The 846's question is "what can you actually sell?" — and asking it before the order, with fresh and honest numbers, is the discipline we build SignalEDI around.
— Chris, founder of SignalEDI
